Elevator car door control system



Jan. 17, 1961 J. J. DREXLER 2,968,366

ELEVATOR CAR DOOR CONTROL SYSTEM Filed Jan. 6, 1959 3 Sheets-Sheet 1 i V F/G.

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PHOTOELECTRI-Q AMPLIFIER i {(4 I I A 4A 2 FIG 2 Z\ i Y by A ml: I INVENTOR. E J N J. DREXL R OH E his ATTORNEYS.

1951 J. J. DREXLER 2, 68,366

ELEVATOR CAR DOOR 00111120 SYSTEM Filed Jan. 6, 1959 5 Sheets-Sheet 2 L, MG L2 SWITCH MOTOR-GENERATOR SET H 2? 300 0| L+| IF MOTOR-GENERATOR CONTROL CIRCUITS E P R AUTOMATIC LEVEILLNG cmcuns oo Z2 1 CARCALL REGISTEENG CIRCUITS 2/ :r V [a 101 I 5% E1 m L 11 1P1. T I

DOOR OPERATING CIRCUITS 001 DE '-H' m AUTOMATIC DISPATCHING CIRCUITS NXT LAi IP11 DE1 I HALL CALL STOP NG CIRCUITS NXT1 30o F/G.4. 3 01 A HALL CALL STOPPING CIRCUITS 1-.--

||CC1 00 o o z 1| k WI INVENTOR. JOHN J. DREXLER his v ATTORNEYS United States Patent ELEVATOR CAR DOOR CONTROL SYSTEM John J. Drexler, Louisville, Ky., assiguor to K. M. White Company, Louisville, Ky., a corporation of Kentucky Filed Jan. 6, 1959, Ser. No. 785,268

14 Claims. (Cl. 18729) 'Ihisinvention relates to elevator control systems and, more particularly, to asystem for opening the door of an operatorless elevator car arriving at the main floor when a passenger is inside the car.

Frequently, in multi-car banks of operatorless elevators more than one car is positioned at the main floor waiting to be dispatched. In order to avoid the possibility of passengers boarding other cars, it is desirable to have the door open only on the next car to be dispatched from the main floor. Accordingly, certain operatorless elevator control systems, such as the one disclosed in the United States patent to White et al., No. 2,854,096, are arranged so that the door of a car arriving at the main floor is opened only in response to registration of a main floor car call unless the car has been selectedfor dispatching.

It has been found, however, that passengers boarding a down-travelling car at upper floors do not invariably register a main fioor car call although it is their intention to leave the car at that floor, apparently assuming that such a call has previously been registered or that such registration is automatic. Consequently, a car carrying passengers can arrive at the main floor in an elevator system of this type without opening its door.

In accordance with the invention, therefore, a new and improved door control means for elevator systems of the above type is arranged to open the door of a car arriving at the main floor with passengers despite the fact that no main floor car call has been registered. On the other hand, if no passengers are in the car, the door remains closed in the usual manner. each car is provided with passenger detecting means and means responsive to the presence of the car in the main floor position indicator zone to initiate door operation.

Further objects and advantages of the invention will be apparent from a reading of the following description in conjunction with the accompanying drawings in which:

Fig. 1 is a diagrammatic plan view of an elevator car utilizing one embodiment of the invention;

Fig. 2 is a diagrammatic view in elevation of an elevator car arranged according to another form of the invention;

Fig. 3 is an electrical schematic circuit diagram of a typical door control circuit adapted for use with the invention;

Fig. 4 is an electrical schematic circuit diagram illustrating the arrangement of a circuit adapted for use with the car shown in Fig. 1;

. Fig. 5 is an electrical schematic circuit diagram showing a representative circuit adapted for use with the car shown in Fig. 2; and

Fig. 6 is a straight line diagram showing the relative location of the relays and contacts illustrated in Figs. 3, 4, and 5, those relays and contacts appearing in Fig. 5 being specifically identified. I

It will be understood that although the invention is described hereinafter with reference to door operation of elevator cars arriving at a main floor, the system is More particularly,.

intended for use at any terminal floor at which more than one car may be parked while awaiting dispatching.

As illustrated in the diagrammatic plan view of Fig. 1, an elevator car 10 provided with the usual door 11 carries a light source 12 in one sidewall 13 and a photocell 14 in the opposite sidewall 15. A beam of radiant energy 16 is directed across the car from the light source 12 to the photocell 14 and a photoelectric amplifier 17 is electrically connected to the photocell in the usual manner to energize the winding of a relay EEX in re sponse to interruption of the beam 16, the relay EEX being deenergized whenever the beam 16 is unbroken.

The light source 12 and the photocell 14 are positioned as far as possible from the door 11 without leaving enough room between the door and the beam 16 to permit a passenger to stand near the door without interrupting the beam. vided with a plurality of light sources and corresponding photocells, arranged so that it would be impossible for a passenger to stand anywhere in the car Without interrupting one of the beams, inasmuch as passengers usually move toward the door of a car when it stops at the main floor, a single beam 16 positioned in the manner described above is adequate for general purposes.

As shown in Fig. 3 of the drawings, the car 10 is driven in the usual manner by a motor-generator set of the type described in United States Patent No. 2,854,- 096, for example, connected between two suitably energized conductors L1 and L2 through a manual switch MG. As described in that patent, two conductors L-I- 4 and L- are connected across the exciter armature and lead to motor-generator control circuits wherein a relay E is picked up when the exciter voltage reaches a predetermined value. These circuits also include a motor and generator fields and brake potential relay P which picks up while the car is running or re-leveling, and a re-leveling relay R which is actuated whenever the car is running, but not re-leveling.

In addition, two individual elevator signal supply conductors 300 and 301 are energized from the conductors L1 and L2 whenever the MG switch is closed and conventional automatic leveling circuits connected between the conductors 300 and 301 include a leveling relay LA. This relay picks up when the car is approaching a floor at low speed and drops out when the car receives a signal to leave the floor.

The usual car call registering means, energized by theconductors 300 and 301, is provided in each car and includes means responsive to actuation by a passenger in the car, such as a manually operable push button designated in accordance with the particular floor represented thereby, as described in Patent No. 2,854,- 096. When a car call push button, for example, the first, or main, floor car call push button 1, is operated. a corresponding floor car call relay 1C is energized through a current limiting resistor 20. When the floor car call relay 1C picks up, it seals itself by closing a normally opened contact 1C1 shunting the car call push button 1. As the car approaches the floor for which the car call is registered, a car call pick up brush 21 contacts a corresponding fioor segment 22, completing a circuit through conventional car call registering circuits and the 1C1 contact to actuate a car call relay CC, this relay being dropped in the usual manner when the car has stopped at the floor.

' Car position indicating circuits of the type described in Patent No. 2,854,096, for example, are also included in elevator systems arranged according to the invention. At the first floor, for example, a brush 30 is energized through a normally opened contact E1 when the motorgenerator set is running and the exciter relay E is picked up. Whenever the car is in the first floor indicator zone,

Although the car 10 could be prothe brush 30 contacts a floor segment 31 corresponding to the position of the car in the hatchw'ay, completing a circuit through an indicating lamp 32 and a first floor position indicating relay 1P1.

Except for the passenger detecting means described hereinafter. the elevator system of the invention includes conventional door operating circuits energized from the conductors 300 and 301 wherein a door operator master pilot relay DE picks up in response to closing of a D01 contact to initiate the door opening operation. These circuits also include a door timer TD arranged to open a TD1 contact to close the doors at a predetermined time after they open, as described in Patent No. 2,854,096. Furthermore, the system utilizes automatic dispatching circuits of the type described in the abovementioned patent to select cars for dispatching from a dispatching floor wherein the selection of a certain car is registered by actuation of a corresponding. next signal relay NXT.

As illustrated in Fig. 4', the relay EEX in the photoelectric amplifier 17 and the photocell 14 are connected across the conductors 300 and 301 in such manner as to pick up the EEX relay whenever the light beam to the photocell 14 is broken, thereby indicating the presence of a passenger in the car. If the car is in the first floor zone, as indicated by closing of the normally opened lPIl contact, is at its lowest leveling speed causing the normally opened LA1 contact to close, and is running but not re-leveling so that the R1 contact is. closed, an interlock relay IDO is picked up, sealing itself through an IDOI contact until operation of the door opens the.

normally closed DEI contact. I

In order to open. the door,.a door open signal relay D'O must be actuated, closing. the normally opened contact D01 in the DE relay circuit shown in Fig. 3. As illustrated in. Fig. {1, the DO relay can be picked up through conventional hall call stopping circuits as the car ap-- proaches a floor at which the hall call has been registered or through a normally opened CCI contact when a; car call for a floor has been registered in the manner described above, picking up the car call relay CC, each of these circuits being completed through the normally closed door timer contact TD1. Whenever the DO relay is actuated, it. seals itself through the normally opened D02 contact until. the door timer contact TD1 is opened at the end oi the predetermined time interval. Also when the car has been parked at a dispatching floor with its door closed andis selected. for next dispatching, actuation of the NXT relay closes a NXT-1 contact to pick up the door open signal relay D through the normally closed TD1 contact.

In conjunction with the embodiment of the invention shown in Fig. 1, the door open signal relay circuit also includes door opening means responsive to the position of the elevator at the main floor and to the presence of apassenger in the car such as a normally opened IDOZ contact and a normally opened EEXI contact connected to actuate the D0 relay when both contacts are closed.

With this arrangement, when a. car is in the main floor position indicator zone, as evidenced by the IP11- When a passenger within'the car interrupts the light beam 16 after the IDO relay is picked up, closingof the IDOZ and EEXI contacts energizes the D0 relay causing, the car door to open by completion of the DE relay circuit through the normally opened D01 contact even though no car call has been registered.

Inasmuch as the IDO relay remains sealed until thedoor opens, it will be apparent that the door can be opened by interruption of the light-beam16 at any time after the IDO relay is picked up. Thus, even though a passenger may stand at the rear of the car while it approaches the main floor and does not move toward the door until after the car has stopped, the door will open when the passenger breaks the beam 16. Also, inasmuch as the normally closed DE1 contact opens when the door opens, the IDO relay cannot be picked up again by a passenger entering the car when the door has opened. On the other hand, if the passenger has depressed the first floor car call button 1, the car call relay CC is picked up, actuating the DO relay in the usual-manner, as soon as the car enters the first floor indicator zone. With no passenger inthe car, the door remains closed after the car arrives at the main floor until it is selected for next dispatching by actuation of the NXT relay closing the NXTI contact.

In the embodiment of the invention shown in Fig. 2, an elevator car 40 having a door 41 is supported by a cable 42 in the usual manner in a hatchway 43, a hall door 44 being; provided at each floor served by the car. According to the invention, the car 40 includes means for detecting the presence of a passenger in the car and this may comprise a conventional stretch-of-cable load weighing device or may be the platform mat type of weighing. device illustrated diagrammatically in Fig. In this arrangement, the car platform 45 is depressible by a predetermined load less than the weight of: one. passenger, for example, fifty pounds, to operate a load weighing switchv LW. In either case, the weighing device includes normally opened contacts which close in response to presence of the predetermined load in the car.

Inasmuch as the load responsive form. of" passenger detecting means is actuatedwhenever a passenger isin the car regardless of his location, no interlock. relay is necessary in this embodiment of the invention. Accordingly, as illustrated in Fig. 4,, the D0 relay circuit utilizedv with a car" of the type. shown in Fig. 2. is. arranged to pick up the DO relay through the normally closed TD1 contact and the conventional hall call stopping circuits, the normally opened car call relay contact CCl, the normally opened next signal relay contact NXTI, as described above, or through a load weighing switch circuit. The latter circuit includes the normally opened. load weighing. switch LW, the first floor position indicator relay contact IP11, the low speed leveling contact LA1, and the R1 contact, which is closed when the car is running but not re-leveling'.

Therefore, if a passenger enters the car 40 at. an upper floor, the load weighing. switchLW closes in response to his added weight. As the car enters the. first floor position indicating. zone, the normally opened IP11 contact closes, and when the car is at low leveling speed, the normally opened LA1 contact is closed in the manner described above. Also, inasmuch as the car is' running. but not re-leveling, the normally opened R1 contact is closed. In this condition, even though no car call has" been registered, the door open signal relay D0 is energized through the normally closed door timer contact TD1 andseals itself through the normally opened contact D02, transferring the normally opened contact D01 to energize the DE relay and initiate the door opening operation. After the door has opened, this circuit cannot be re-established by entry of a passenger, since the RAI contact remains in its normally opened position when the elevator is" not running.

If the main floor car call button 1 has been operatedhy the passenger when he enters, the car c'all relay CC is picked up in the usual manner as the car enters the. first floor position indicating zone to actuate the D0 relay and open the door. Also, if there is no passenger in the car, the door remains closed in the usual manner until the NXT 1 contact closes upon actuation of the NXT relay in the automatic dispatching circuits. 4

It will be apparent that a plurality of photoelectric passenger detecting. devices of the type shown in Fig. l

could be arranged in the car so that at least one radiant energy beam is interrupted by any passenger at any location in the car to actuate the EEX relay of Fig. 1. With this arrangement, no interlock relay is necessary and the EEXl contact can be substituted for the LW contact in the circuit of Fig. 5.

Although the invention has been described herein with respect to specific embodiments, many modifications and variations therein will readily occur to those skilled in the art. Accordingly, all such variations and modifications are included within the intended scope of the invention as defined by the following claims.

I claim:

1. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor, passenger detecting means responsive to the presence of a passenger in the car, and door control means responsive to operation of the position indicating means and the passenger detecting means to open the car door upon arrival at the selected floor only if the presence of a passenger is detected.

2. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor, leveling means operable to position the car at the selected floor, passenger detecting means responsive to the presence of a passenger in the car, and door control means responsive to operation of the position indicating means, the leveling means and the passenger detecting means to open the car door upon arrival at the selected floor only if the presence of a passenger is detected.

3. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor, leveling means operable to position the car at the selected floor, running means actuable whenever the car is running except when the car is re-leveling, passenger detecting means responsive to the presence of a passenger in the car, and door control means responsive to operation of the position indicator means, the leveling means, the running means, and the passenger detecting means to open the car door upon arrival at the selected floor only if the presence ofa passenger is detected.

4. In an elevator car door control system having leveling means operable to position the car at a selected floor, passenger detecting means responsive to the presence of a passenger in the car, and door control means responsive to operation of the passenger detecting means and of the leveling means at the selected floor to open the car door upon arrival at the selected floor only if the presence of a passenger is detected.

5. In an elevator car control system wherein more than one car may be parked at a dispatching floor awaiting dispatching and wherein the door of an empty car normally remains closed upon arrival at the dispatching floor until the car is selected for dispatching, passenger detecting means responsive to the presence of a passenger in a car, means responsive to the arrival of the car at the dispatching floor, and door control means responsive to the passenger detecting means and the dispatching floor arrival means to open the car door upon arrival at the dispatching floor only if the presence of a passenger is detected.

6. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor, photoelectric means responsive to the presence of a passenger in the car, and door control means responsive to operation of the position indicating means and the photoelectric means to open the car door upon arrival at the selected floor only if the presence of a passenger is detected.

7. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor,

radiant energy beam means generating at least one radiant energy beam extending across the car, photoelectric means responsive to interruption of the beam, and door control means responsive to operation of the position indicating means and the photoelectric means to open the car door upon arrival at the selected floor only if the radiant energy beam is interrupted.

8. An elevator car door control system comprising car position indicating means actuable when'the car is within the position indicator zone of a selected floor, radiant energy beam means generating at least one radiant energy beam extending across the car at a position spaced as far as possible from the car door without permitting a passenger to stand between the beam and the door, photoelectric means responsive to interruption of the beam, and door control means responsive to operation of the position indicating means and the photoelectric means to open the car door upon arrival at the selected floor only if the radiant energy beam is interrupted.

9. An elevator door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor, leveling means operable to position the car at the selected floor, interlock means operable in response to actuation of the car position indicating means and the leveling means and releasable upon opening of the car door, radiant energy beam generating means generating a radiant energy beam extending across the car at a position spaced as far as possible from the car door without permitting a passenger to stand between the beam and the door, photoelectric means responsive to interruption of the beam, and door control means responsive to operation of the interlock means and the photoelectric means to open the car door.

10. In an elevator car control system wherein more than one car may be parked at a dispatching floor awaiting dispatching and wherein the door of an empty car normally remains closed upon arrival at the dispatching floor until the car is selected for dispatching, interlock means actuable upon arrival of a car at the dispatching floor and releasable upon opening of the car door, radiant energy beam generating means generating a radiant energy beam extending across the car at a position spaced from the door, photoelectric means responsive to interruption of the beam, and door control means responsive to operation of the interlock means and the photoelectric means to open the car door.

11. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected floor, load weighing means responsive to the weight of one passenger in the car, and door control means responsive to actuation of the position indicating means and the load weighing means to open the car door upon arrival at the selected floor only if at least one passenger is detected by the load weighing means.

12. In an elevator car door control system having leveling means operable to position the car at a selected floor, load weighing means responsive to the weight of one passenger in the car, and door control means responsive to operation of the leveling means and the load weighing means to open the car door upon arrival at the selected floor only if at least one passenger is detected by the load weighing means.

13. An elevator car door control system comprising car position indicating means actuable when the car is within the position indicator zone of a selected fioor, load weighing means comprising platform mat means responsive to the weight of one passenger in the car, and door control means responsive to actuation of the position indicating means and the load weighing means to open the car door upon arrival at the selected floor only if at least one passenger is detected by the load weighing means.

14. In an elevator car control system wherein more than one car may be parked at a dispatching floor await- 3' ing dispatching and :a'vherein *the door :of an empty ear normally-remains closegi upon arrival at the dispatching floor until -the car is selected for dispatchingioad weighin}; means responsive to the presence of a passenger-"in a car, means responsive to the arrival of the car 'at "the dispatching floor, and door control means ICSPQHSiVe to t load w hin m ans an th is ai h n' floo rival means to open the car door upon arrival af'jhadisby the load weighing zRe xanccs:Q adainrithc filepifthis aten't;

UNITED .Santini EBL san im 

